高层钢结构施工过程时变模型理论与跟踪监测

Time Dependent Model Theory and Track Monitoring for Construction Process of High-Rise and Steel Structural Building

针对混凝土的时变变形对钢管混凝土组合结构施工过程中结构受力的影响,基于CEB-FIP中的混凝土时变模型,提出了对钢管混凝土组合高层框架结构进行施工过程计算的时变模型,以考虑结构的施工顺序和诸如混凝土的收缩、徐变等时变效应的影响以反映此类结构的真实特性.通过某21层钢混组合高层框架结构的数值模拟与现场监测结果的对比表明:提出的分析模型能够真实反映结构复杂的施工过程及材料时变特征和结构几何非线性对结构性能的影响,数值模拟结果表明混凝土收缩和徐变引起的结构变形在高层结构设计中不容忽视.

In view of the influence of time-dependent deformations of concrete on steel tube and concrete composite structures in the construction process, this paper presents a time-dependent analysis model for high-rise building with concrete filled steel tube （CFST） considering the construction sequences and the time-dependent effect such as the shrinkage, creep of concrete, which can reflect the real behavior of structures in the construction process. Finally, numerical results of a 21-story steel and concrete composite frame structure are compared with those obtained from spot monitoring test, which prove that the analytical model can reflect the structural effects of a complex construction process as well as the geometry nonlinear and time dependent behavior of the materials. And the numerical simulation results show that the deformation of the structure caused by shrinkage and creep of concrete during construction can not be ignored in the design of high-rise building structures.